Connecting odoo to AWS rds postgres dataabse

I was trying to connect to odoo to AWS RDS postgres 9.6 based database for better scalibilty. I have changed the /etc/odoo.conf file according to required config parameters but on restarting bahmni I am being shown database selector webpage on accessing odoo.

These are the performed changes in odoo.conf file:
[options]
; This is the password that allows database operations:
admin_passwd = Adm!n123
db_host = RDS_POSTGRES_DNS.amazonaws.com
db_port = 5432
db_user = odoo
db_password = RDS_PASSWORD
addons_path = /opt/bahmni-erp/bahmni-addons,/opt/bahmni-erp/odoo/addons,/usr/lib/python2.7/site-packages,/opt/bahmni-insurance-addons/
logfile = /var/log/odoo/odoo.log
log_level = error

P.S: I am able to connect to RDS databse from my bahmni instance via other postgres client.So connection is getting successful

What extra changes are required in order to make this work?

HELP REQUIRED

try using a postgres client (psql) from the appserver instance first to check whether you can connect and query

Yeah I have checked it, connection is successful and can perform all database operation via the postgres client on the AWS RDS postgres database.

Please help with any additional required config changes(If any)